1. Field of the Disclosure
The disclosure relates generally to systems for measuring physical characteristics of a bodily vessel, and more particularly to surgically embedded magnetoelastic sensors for measuring physical characteristics.
2. Brief Description of Related Technology
Stents are typically mesh tubular structures that impart and maintain patency in a variety of vessels and ducts that have become constricted as a result of stenotic pathology. Although the act of implanting a stent relieves symptoms caused by the constriction, in-stent restenosis, i.e., the reappearance of cavity narrowing, typically due to the reaction of the body to the presence of the stent, is a risk associated with all stenting procedures.
An example of a stent application area is the bile duct, which transports bile between the liver, gall bladder, pancreas, and small intestine. The constriction relieved by stent implantation is often due to pancreatitis, cholangitis, tumors, or gallstones. Restenosis can occur in an average of 4-5 months via formation of a bacterial matrix known as biliary “sludge.” See, e.g., G. Donnelli, et al., “Plastic Biliary Stent Occlusion: Factors Involved and Possible Preventive Approaches,” Clinical Medicine & Research, Vol. 5, No. 1, 2007, pp. 53-60.
The timeframe for clinically significant restenosis to occur varies from case to case. Current techniques for diagnosing a blockage are indirect and rely on detecting enzyme levels that may not increase until after the blockage is significant. The combined effect of the unknown pathogenesis time course and the indirect testing methods can result in either unnecessary, prescheduled interventions or in untimely interventions after patients exhibit outward symptoms of the blockage (and liver damage has already occurred). As such, a direct method of diagnosis would enable timely intervention and eliminate unnecessary procedures.